<template>
  <div id="app">
    <div class="container">
      <!-- 顶部框模块 -->
      <div class="form-group">
        <div class="input-group">
          <h4>品牌管理</h4>
        </div>
      </div>

      <!-- 数据表格 -->
      <table class="table table-bordered table-hover mt-2">
        <thead>
          <tr>
            <th>编号</th>
            <th>资产名称</th>
            <th>价格</th>
            <th>创建时间</th>
            <th>操作</th>
          </tr>
        </thead>
        <tbody>
          <tr v-for="item in list" :key="item.id">
            <td>{{ item.id }}</td>
            <td>{{ item.name }}</td>

            <td :class="{ red: item.price > 100 }">
              {{ item.price }}
            </td>
            <td>{{ item.time | getData }}</td>
            <!-- //#返回顶部 -->
            <td><a href="#" @click.prevent="delFn(item.id)">删除</a></td>
          </tr>
          <!-- 不用循环 总价和平均价   当list数组数量不为0 的时候  才显示统计的结果 -->
          <!-- 不用循环，展示总价 和 平均价 -->
          <tr v-show="list.length !== 0" style="background-color: #eee">
            <td>统计:</td>
            <td colspan="2">总价钱为:{{ sum }}</td>
            <td colspan="2">平均价:{{ junjia }}</td>
          </tr>
        </tbody>
        <!-- 底部的提示消息 -->

        <tfoot v-show="list.length === 0">
          <tr>
            <td colspan="5" style="text-align: center">暂无数据</td>
          </tr>
        </tfoot>
      </table>

      <!-- 添加资产 -->
      <form class="form-inline">
        <div class="form-group">
          <div class="input-group">
            <input
              type="text"
              class="form-control"
              placeholder="资产名称"
              v-model="name"
            />
          </div>
        </div>
        &nbsp;&nbsp;&nbsp;&nbsp;
        <div class="form-group">
          <div class="input-group">
            <input
              type="text"
              class="form-control"
              placeholder="价格"
              v-model.number="price"
            />
          </div>
        </div>
        &nbsp;&nbsp;&nbsp;&nbsp;
        <!-- 阻止表单提交 -->
        <button class="btn btn-primary" @click.prevent="addFn">添加资产</button>
      </form>
    </div>
  </div>
</template>

<script>
import moment from "moment";
export default {
  data() {
    return {
      name: "", // 名称
      price: 0, // 价格
      list: JSON.parse(localStorage.getItem("dList")) || [],
    };
  },

  filters: {
    getData(time) {
      return moment(time).format("YYYY-MM-DD HH:mm:ss");
    },
  },
  methods: {
    addFn() {
      //判断是否有内容
      if (this.name.trim().length === 0 || this.price <= 0) {
        return alert("输入正确信息");
      }

      //unshift()添加到最前面   给list的数组添加数据
      this.list.unshift({
        id: +new Date(),
        name: this.name,
        price: this.price,
        time: new Date(),
      });
      this.name = "";
      this.price = "";
    },
    delFn(id) {
      this.list = this.list.filter((item) => item.id !== id);
    },
  },
  computed: {
    sum() {
      //总价
      return this.list.reduce((sun, obj) => (sun = sun + obj.price), 0);
    },
    junjia() {
      return (this.sum / this.list.length).toFixed(2);
    },
  },
  watch: {
    list: {
      handler(newa, old) {
        localStorage.setItem("dList", JSON.stringify(this.list));
      },
      deep: true,
    },
  },
};
</script>

<style>
.red {
  color: red;
}
</style>
